Spark arrester and protector for exhaust pipes



Jan. 15, 1952 c. H. HARMON 2,582,905

SPARK ARRESTER AND PROTECTOR FOR EXHAUST PIPES Filed Oct. 24. 1947Patented Jan. 15, 1952 SPARK ARRESTER AND PROTECTOR FOR EXHAUST PIPESCline Harry Harmon, Waterloo, Iowa, assignor to Waterloo FoundryCompany, Waterloo, Iowa,

a copartnership Application October 24, 1947, S erial No. 781,859

(01. ss-ss) 2 Claims.

The present invention relates to a spark arrester and extinguisher,particularly adaptable to the exhaust pipe of a farm tractor, butapplicable also to use with stationary engines of all types.

Engines emit sparks through their exhaust pipes and this is particularlydangerous in case of farm tractors where the sparks can set fire tograin in the fields, and to buildings when used therein.

An object, therefore, of the present invention is the provision of anovel spark arrester and extinguisher, which can be attached to anexhaust pipe.

Another object is the provision of a simple device which is simple inoperation and does not offer material resistance to the flow of exhaustgases from the'exhaust pipe.

A further object is the provision of a spark arrester and extinguisherso constructed and arranged that the exhaust gases and any sparkscarried thereby are directed against a bafile member or shield whereinthe impact of the sparks against the baflie member extinguishes thesparks.

The device of the present invention is a generally cone-shaped device,constructed with an open base for receiving exhaust gases from theexhaust pipe, and having a-closed axial outward end and a transverseopening therebetween. The device is provided with vanes to prevent thegases from swirling, and thereby to direct them axially outward againstthe closed outer end of the device.

A further object of the invention is the provision of a novel sparkarrester and extinguisher which, when applied to a vertical exhaustpipe, prevents rain and foreign matter from entering the exhaust pipe.Most exhaust pipes on farm tractors today are arranged vertically.

Still another object is the provision of such a device as describedabove, which is exceedingly simple in construction. The major partsmaking up the devices are simple castings.

A still further object is the provision of such a device as describedabove, which is economical, both in the material used therein, and itsmanufacture.

With these and other objects in view, my invention consists in theconstruction, arrangement, and combination of the various parts of mydevice whereby the objects contemplated are attained, as hereinaftermore fully set forth, pointed out in my claims, and illustrated in theaccompanying drawings, wherein;

Figure 1 is a side view of the novel spark arrester of the presentinvention secured to an exhaust pipe;

Figure 2 is a bottom view of the device; and

Figure 3 is an enlarged vertical axial sectional view of the device.

Referring now in detail to the drawings, the device as a whole isindicated at l2, applied to exhaust pipe M of a tractor. The exhaustpipe it, it will be observed, is arranged vertically as most exhaustpipes on farm tractors are arranged today. The device includes a mainmember it, which is-in the shape of a hollow truncated cone, having anopen base or large end l8, and an open small end 2|], the two endsfurnishing an axial passage therethrough. The member I6 is in eiiect abaffle member and may be so termed.

A plurality of axially extending supporting legs 22 is formed on theinner surface of the wall of the cone member l6 intermediate the largeand small ends thereof, and spaced circumferentially therearound. In thepresent instance, three such supporting legs are provided, although theparticular number employed may be varied, if desired. The supportinglegs 22 are preferably cast integral with the cone member I6, and may beof any desired shape, such as rectangular in cross section, asillustrated herein. The lower ends of the supporting legs 22 areprovided with threaded openings for the reception of bolts 24 and locknuts 26. The bolts 24 are arranged radially and are adapted to bearagainst the exhaust pipe l4 when the device is applied thereto, and thesupporting legs 22 are positioned around the periphery of the end of theexhaust pipe. The supporting legs 22 are illustrated as being axiallydisposed, but other shapes may be employed, so long as they are adaptedto fit around the exhaust pipe.

Strengthening webs 28 are formed between the supporting legs 22 and thewall of the cone member 16 below the point of juncture between thesupporting legs and the well. These webs 28 may be of small dimension inthickness, their purpose being to strengthen the supporting legs 22. v

A plurality of vanes 30 are also formed integrally with the cone memberIt in the casting thereof. The vanes 30 are arranged radially and areformed on the vertical supporting legs 22 and the 'Wall of theconemember 16 above the point of juncture between the latter. The upperends of the vanes 30 in the present instance are flush with the uppersmall end 20 of the cone member be made to extend radially inwardlytoward each other to a greater or lesser extent than that illustrated. Asecond cone shaped hollow member 32-is employed, which may also bereferred to as a baffle member. The cone member 32 is"a1 so a casting" Iand differs from the cone member IS in that the former is not truncated.Formedintegrally with the cone member 32 on the inner surface thereofare a plurality of lugs 34 extendin gen: erally downwardly or axiallyfrom the cone member. In the present instance the lugs 34 divergeoutwardly downwardly and have a peculiar shape adapted to cooperate withthe upper small end of the truncated cone member [6. The marginal edgeoftheupper smaller end 20 of the cone member 'IS'is provided withaplurality of notches 36 on the inner side thereof for receiving the lugs34. The lower ends of the lugs 34 are swaged at aa'cagainst the innersurface of the wall of the cone member I6, for securing the member 32 tothe member 3.. a

The upper cone member-'32, which may also be termed a shield, is ofgreater diameter than the upper small end of the truncated cone memb r 6t er o m n Open n 0 The. whole device, including the cone meme; Is, andthe cone shaped shield 32, is'it glf generally cone shaped, having atransverse open ing 40 intermediate the ends. It will be understood thatalthough cone shaped members are employed in the presentinstance, othershapes may be employed as well, such as square, hexa:

,gonal, etc., the chief characteristic being that the device convergesoutwardly axially pf the. exhaust pipe.

In applying the device to an exhaust pipe, the supporting le s 22 ositoa d armindih periphery of the outer end of the exhaust pipe,

.andthe bolts turned n against the ipe The locknuts 26 insure that theboltswill remain ti ht against the exhaust pipe. The vanes are soarranged and extend radiallyinwardly sufl'iciently that they engage theupper edge of t e ex u t i The nes .30- th e r se ve as stops tolimitthe movement of the devioeonto the exhaust pipe.

Exhaust gases emerging from v the exhaust pipe and entering thedeviceare "prevented from swirling by the vanes 30. Thereimay be a tendency'forthe gasestoswirl, and insodoing may emerge out the opening 40 withoutcoming into contact with the inner surface ofjthedevice and especiallythe shield 3 2. The vanes 3U baffletl'ie exhaust gases and direct themaxially through the device and the gases thereforehmpingefon the innersurface of thecone shaped shieldi32.

Thereafter, of course,' the gases' do leifiei e through the opening 40,but the impact ofian'y sparks" which may "be in the exhaust gases on thesurface of 'the" shield" 3 2" extinguishes" sparks. V

e mo hifhe d e. sr eer l agg h 4 a a vertical exhaust pipe, it can, ofcourse, be applied to horizontal exhaust pipes as well. When applied toa vertical exhaust pipe, the device effectively prevents the entrance ofrain and other foreign matter into the pipe.

The device is of simple construction, being made up of two simplecastings, with the excepti on of thebolts, and the two castings areeasily secured together fbfa simple operation.

While I have herein shown and described a preferred embodiment of myinvention, manifestly it issusceptible of modification and rearrangementof the parts without departing from thespirit and scope thereof. I donot, therefore,- wish to be understood as limiting my invention to theprecise form herein disclosed,

except "as'I may be so limited by the appended claim I'claim as myinvention:

1. In a spark arrester, a hollow truncated cone shape member having anaxial passage therethrough, a plurality of supporting legs secured tothe inner surface of and extending substantially axially out of thelarge end of said truncated member, said supporting legs beingadaptedfor positioning around the' outer periphery of the end of anexhaust pipe for securing the device thereto, a plurality of radiallyand axially 'extending vanes secured to the inner surface of saidtruncated member, said vanes "extending a substantial distance radiallyinwardly of said legs, and a hollow cone shape member secured to andhaving its concave side directed toward the small end of saidtruncatedmember, there being a transverse opening between said mem bers.

2. A device of the class described, composed of cast pieces, comprising,a' hollow truncated cone shape member having itsaxial ends open, aplurality of supporting legs formed on the inner surface of said memberand extending substantially axially out of the large end thereof,saidsupporting legs being spaced circumferentially and adapted to bepositioned around the periphery of the end of an exhaust pipe forsecuring the device thereto, axial vanes formed on said supporting legsand-extending radially inwardly therefrom, said vanes being sopositioned as toengage the end of the exhaust pipe and extend,intotheprojectionof the interior thereof, and a hollow cone shape shieldmem- EF R NQ CI D The following references are of record in the file ofthis patent:

UNITEDHISTATES PATENTS Number Name Date 179,147 Auld June 27, 1876499,904 Bradley June 2 0, 1893 915,871 Merrill Mar. 23, 1909 21,277,932vHosbein Mar. 31, 194.2 2,491,902 Brown et al, June 11, 1946

